Objective To investigate the variation in the position of conus medullaris in Chinese adult population in order to avoid hitting conus during spinal puncture. Methods Eight hundred patients suffering from back pain, aged 18-91 yr, were enrolled in this study. The position of conus medullaris was determined using Siemens 1.5 T magnetic resonance imaging system. According to the method described by Reimann, the vertebral body was used as mark of reference to the level of the end of conus. Results There were 190 patients in whom the position of the end of conus medullaris was lower than L1,2 . The incidence of the position of the end of conus medullaris lower than L1,2 was higher in patients 30-60 or older than in those under 30, and in those over the age of 60 than in those 30-60 (P ＜ 0.05). Conclusion Spinal puncture should be performed cautiously at L2,3. CT or MRI is recommended before operation for the patients to locate the position of conus medullaris and avoid injury to the spinal cord.

Objective To analyze the clinical characteristics of hospital acquired mycotic pneumonia in elderly patients (aged≥ 80 years).Methods The clinical data were reviewed on 64 cases of elderly patients aged 80-93 years with hospital-acquired infection of mycotic pneumonia from June 2007 to July 2011.According to the results of sputum culture,therapy plan was made and antibiotic drugs were selected.Results Among these 64 patients,Candida mycoderma (62.5 ％,40 cases) occupied the first place and C.glabrata (20.3％,13 cases) was the second place (x2 =127.50,P＜0.01).Their chest x-ray or CT films were not characteristic,but lamellar shadows (68.8％,44cases) and cotton-like shadows (40.6 ％,26 cases) were found in the majority.60 cases (93.8 ％ ) of these patients had more than 3 complications,and 58 cases (90.6％) of them took over 2 kinds of antibiotics.The improvement rate of these patients was 81.3％ (52 cases)and mortality rate was 18.8％(12 cases).Conclusions Elderly patients (aged≥ 80 years) with hospital acquired infection of mycotic pneumonia have high incidence and mortality rate.The key point to cure is to make an early diagnosis and treat them as early as possible.

Objective To investigate apoptosis of HepG2 ceils after transfecfion with LIGHT gene and interferon-γ. Methods LIGHT gene and interferon-γ were transfected into HepG2 cells by liposome mediated method. The HepG2 cells were divided into group A (transfected with LIGHT gene or interferon-γ), group B (transfeeted with LIGHT gene and interferon-γ) and group C (non-transfection group). The apoptosis rate of the HepG2 cells and the expression of Bcl-2 and Caspase-8 were detected 12, 24, 48 hours after transfeetion. Results (1) The apoptosis rates of HepG2 cells at hour 12, 24 and 48 after transfeetion were 18.8% ± 3.5%, 25.7%± 2.8% and 36.4% ±3.6% in group A, 23.8% ±2.4%, 31.1% ±2.1% and42.5% ±4.5% in group B, and 8.7% ± 2.1%, 9.3% ± 1.6% and 10.9% ± 1.2% in group C. There was a significant difference in apoptosis rate among the 3 groups (F = 15.69, 53.33, 48.28, P < 0.01). (2) The expression of Bcl-2 in HepG2 cells at hour 12, 24 and 48 after transfection was 16.4% ± 5.0%, 13.4% ± 3.5% and 8.6% ± 2.3% in group A, 14.7%±3.8%, 9.1% ±2.0% and 4.6% ±2.0% in group B, and 25.3% ±6. 3%, 19.8% ±4.4% and 10.1% ±3.8% in group C. There was a significant difference in the expression of Bcl-2 among the 3 groups (F = 6.19, 12.29, 5.81, P <0.05). (3) The expression of Caspase-8 at hour 12, 24 and48 after transfection were 19.3% ±2.4%, 27.2% ±1.9% and 33.7% ±3.0% in group A, 22.7% ±2.2%, 30.9% ±3.1% and 38.2% ±3.2% in group B, and 1.2% ±0.8%, 1.8% ±0.6% and 3.2% ±1.5% in group C. There was a significant difference in the expression of Caspase-8 among the 3 groups (F =71.54, 112. 78, I01.61, P < 0.01). Condusions LIGHT gene can signiticanfly promote cell apoptosis through regulating the expression of Bcl-2 and Caspase-8. Interferon-γ enhanced the effect of LIGHT gene on the apoptosis of HepG2 cells.

Objective To investigate the protective effects of Angelicae Sinensis Radix and Angelicae Sinensis Radix polysaccharides on immune function injury induced by X rays in SD rats. Methods Forty SD rats were randomly divided into control group, model group, Angelicae Sinensis Radix Decoction group, Angelicae Sinensis Radix polysaccharide group and positive medicine group. After routine feeding for 14 day, each administration group was given relevant medicine for gavage, while control group and model group were given the same amount of distilled water for gavage, once a day for 7 d. From the 8th day, except for the control group, the rats in the rest of groups were subjected to whole-body X ray irradiation, continuous exposure to 2 d; the total absorbed dose was 6 Gy. The rats were killed by femoral artery after irradiate 3 d. The WBC count, RBC, HGB, and PLT in peripheral blood were observed by blood routine test; the number of nucleated cells in the bone marrow was observed by nucleated cell count method; the pathological changes of spleen were observed by HE staining under microscope; the contents of IFN-γ and IL-4 in serum were detected by ELISA. Results Compared with the control group, the spleen index WBC, number of bone marrow nucleated cells and serum contents of IL-4 and IFN-γ in model group was significantly lower (P<0.05), The contents of RBC and HGB increased (P<0.05). Compared with the model group, WBC, number of bone marrow nucleated cells, and the contents of IL-4 and IFN-γ in serum of each administration group increased significantly (P<0.05); RBC and HGB decreased significantly (P<0.05). Conclusion Angelicae Sinensis Radix and Angelicae Sinensis Radix polysaccharides have protective effects on the immune function injure induced by X ray in SD rats.

Objective To analyze indications,complications and outcomes of amputation.Methods A total of 15 patients undergone amputation in field or at tent hospital were collected for analy-zing injury severity,place where amputation was done,whether open or closed amputation and stitch re-moval time. Results There were 9 males and 6 females.at an average age of 32 years(11-51years).There were 16 amputations including Gustilo IIIB in 2 patients, Gustilo IIIC in 9 and Tscheme Ⅲin 5 according to Gustiln classification or Tscheme classification.Four patients who received amputation in field or at tent hospital developed infection and had to receive amputation again at a higher level on the limb and drainage of open wounds because of a higher infection rate due to the amputation location.Ten patients received first amputation at higher levels with open wound at station hospital but only 2 manifested infected incision.High level amputation with one stage closure was done in 1 patient who was infected and suppurated after operation and even developed bacteremia. Conclusions Infection rate following am-putation 4n field and tent clinics is rather higher,so secondary open amputations should be performed at a higher level as soon as possible.One-time and high-level open amputation plays an important role in treat-ment of severe lower limb injuries following earthquake.

Hemophagocytic syndrome，synonymous with hemophagocytic lymphohistiocytosis（HLH），represent a spectrum of hyperinflammatory response syndromes that have been the subject of intense scrutiny in terms of their etiopathogenesis and early warning strategies.Ebstein-Barr virus（EBV）-associated HLH is the most prevalent form of infection-associated secondary HLH.It is characterized by a sudden onset，rapid progression，and high mortality rate.The primary clinical features include persistent fever，often accompanied by manifestations of multi-system involvement，such as cytopenias，hepatosplenomegaly，lymphadenopathy，abnormal liver function，respiratory symptoms，neurological symptoms，and rashes.Therefore，early recognition and warning are crucial for improving the prognosis of patients with EBV-HLH.This article aimed to focus on the relationship between EBV and HLH，the diagnosis of EBV-HLH，associated warning factors，and treatment strategies.

Objective To investigate the effects of cholesterol-lowering probiotics, DM9054 com-bined with 86066, on the intestinal mucosal barrier and gut microbiota in mice with nonalcoholic fatty liver disease ( NAFLD) induced by high-fat diet and the possible mechanisms. Methods Twenty-four male mice deficient in the low-density lipoprotein receptor gene ( Ldlr- / - mice ) were randomly divided into three groups including control, NAFLD model and probiotic intervention groups. Mice in the three groups were given normal chow diet+normal saline, high-fat diet ( HFD)+normal saline, and HFD+cholesterol-lowering probiotics, respectively. The mouse model of NAFLD was established by feeding mice with high-fat diet (45％ of calories derived from fat diet) for 12 weeks. qPCR was performed to measure the expression of liv-er and intestinal inflammatory genes and liver cholesterol synthesis genes. Western blot assay was used to de-tect the expression of intestinal tight junction proteins and HMG-CoA reductase ( HMGCR ) . Pathological changes in tissues were evaluated by HE staining. Features of gut microbiota were analyzed by 16S rRNA gene sequencing. Results Cholesterol-lowering probiotics intervention attenuated HFD-induced hepatic steatosis, inflammatory responses and obesity and decreased the synthesis of liver cholesterol (P<0. 05). Moreover, inhibited gut inflammatory responses and improved intestinal barrier function were detected in the probiotic intervention group (P<0. 05). The composition of gut microbiota in mice of the probiotic intervention group was different from that of the model group, but similar to that of the control group. Con-clusions Cholesterol-lowering probiotics might attenuate NAFLD in mice through reducing liver cholesterol synthesis, alleviating liver and intestinal inflammation, improving intestinal mucosal barrier function and reg-ulating intestinal microbiota.

BACKGROUND:Osteosarcoma has a complex pathogenesis and a poor prognosis.While advancements in medical technology have led to some improvements in the 5-year survival rate,substantial progress in its treatment has not yet been achieved. OBJECTIVE:To screen key molecular markers in osteosarcoma,analyze their relationship with osteosarcoma treatment drugs,and explore the potential disease mechanisms of osteosarcoma at the molecular level. METHODS:GSE99671 and GSE284259(miRNA)datasets were obtained from the Gene Expression Omnibus database.Differential gene expression analysis and Weighted Gene Co-expression Network Analysis(WGCNA)on GSE99671 were performed.Functional enrichment analysis was conducted using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes separately for the differentially expressed genes and the module genes with the highest positive correlation to the disease.The intersection of these module genes and differentially expressed genes was taken as key genes.A Protein-Protein Interaction network was constructed,and correlation analysis on the key genes was performed using CytoScape software,and hub genes were identified.Hub genes were externally validated using the GSE28425 dataset and text validation was conducted.The drug sensitivity of hub genes was analyzed using the CellMiner database,with a threshold of absolute value of correlation coefficient|R|>0.3 and P<0.05. RESULTS AND CONCLUSION:(1)Differential gene expression analysis identified 529 differentially expressed genes,comprising 177 upregulated and 352 downregulated genes.WGCNA analysis yielded a total of 592 genes with the highest correlation to osteosarcoma.(2)Gene Ontology enrichment results indicated that the development of osteosarcoma may be associated with extracellular matrix,bone cell differentiation and development,human immune regulation,and collagen synthesis and degradation.Kyoto Encyclopedia of Genes and Genomes enrichment results showed the involvement of pathways such as PI3K-Akt signaling pathway,focal adhesion signaling pathway,and immune response in the onset of osteosarcoma.(3)The intersection analysis revealed a total of 59 key genes.Through Protein-Protein Interaction network analysis,8 hub genes were selected,which were LUM,PLOD1,PLOD2,MMP14,COL11A1,THBS2,LEPRE1,and TGFB1,all of which were upregulated.(4)External validation revealed significantly downregulated miRNAs that regulate the hub genes,with hsa-miR-144-3p and hsa-miR-150-5p showing the most significant downregulation.Text validation results demonstrated that the expression of hub genes was consistent with previous research.(5)Drug sensitivity analysis indicated a negative correlation between the activity of methotrexate,6-mercaptopurine,and pazopanib with the mRNA expression of PLOD1,PLOD2,and MMP14.Moreover,zoledronic acid and lapatinib showed a positive correlation with the mRNA expression of PLOD1,LUM,MMP14,PLOD2,and TGFB1.This suggests that zoledronic acid and lapatinib may be potential therapeutic drugs for osteosarcoma,but further validation is required through additional basic experiments and clinical studies.

ObjectiveTo investigate the infection of mouse norovirus (MNV) in experimental mice raised under natural conditions from 19 biological companies in Beijing. MethodsThe mice used in this study were randomly selected from mice produced by 19 companies, and 14 mice of each strain and batch were combined into one cage, totaling 1 396 cages of 19 544 mice. The fecal samples from BALB/c, C57BL/6, ICR, KM, and BALB/c-nude mice were collected. TaqMan probe fluorescence quantitative PCR method was used to detect MNV infection of mice with MNV-1 primer, and whether the mice were infected with MNV was determined according to cycle threshold (Ct value). The chi-square test was used to analyze the difference of positive rate among the fecal samples from the five types of mice. The Ct values of the positive samples were statistically described; the non-parametric test was used to analyze the differences in Ct values among the five types of mice. Results A total of 1 396 fecal samples were collected. The positive rates of fecal MNV detection in BALB/c, C57BL/6, ICR, KM, and BALB/c-nude mice were 17.65%, 39.33%, 10.57%, 18.32% and 27.4%, respectively. According to the chi-square test results, the positive rate of fecal in C57BL/6 mice was higher than that in BALB/c, ICR, and KM mice (all P<0.05), and the positive rate of BALB/c-nude mice was higher than that in ICR and BALB/c mice (P<0.001, P＜0.05) . The viral load of BALB/c-nude or C57BL/6 mice was generally greater than that of KM mice (P<0.05). ConclusionMNV-1 primers can be applied to the detection of MNV infection in mice. The positive rate of MNV in five types of experimental mice in Beijing ranges from 10% to 40%, among which C57BL/6 mice and BALB/c-nude mice have higher positive rates of MNV than the others.

Ankylosing spondylitis (AS) combined with lower cervical fracture is often categorized into unstable fracture, with a high incidence of neurological injury and a high rate of disability and morbidity. As factors such as shoulder occlusion may affect the accuracy of X-ray imaging diagnosis, it is often easily misdiagnosed at the primary diagnosis. Non-operative treatment has complications such as bone nonunion and the possibility of secondary neurological damage, while the timing, access and choice of surgical treatment are still controversial. Currently, there are no clinical practice guidelines for the treatment of AS combined with lower cervical fracture with or without dislocation. To this end, the Spinal Trauma Group of Orthopedics Branch of Chinese Medical Doctor Association organized experts to formulate Clinical guidelines for the treatment of ankylosing spondylitis combined with lower cervical fracture in adults ( version 2024) in accordance with the principles of evidence-based medicine, scientificity and practicality, in which 11 recommendations were put forward in terms of the diagnosis, imaging evaluation, typing and treatment, etc, to provide guidance for the diagnosis and treatment of AS combined with lower cervical fracture.